21161201 has 4 divisors (see below), whose sum is σ = 21279600. Its totient is φ = 21042804.

The previous prime is 21161191. The next prime is 21161227. The reversal of 21161201 is 10216112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21161201 - 2⁶ = 21161137 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21161281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58931 + ... + 59288.

It is an arithmetic number, because the mean of its divisors is an integer number (5319900).

Almost surely, 2^21161201 is an apocalyptic number.

It is an amenable number.

21161201 is a deficient number, since it is larger than the sum of its proper divisors (118399).

21161201 is a wasteful number, since it uses less digits than its factorization.

21161201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118398.

The product of its (nonzero) digits is 24, while the sum is 14.

The square root of 21161201 is about 4600.1305416260. The cubic root of 21161201 is about 276.5965576132.

Adding to 21161201 its reverse (10216112), we get a palindrome (31377313).

The spelling of 21161201 in words is "twenty-one million, one hundred sixty-one thousand, two hundred one".